Most mainstream distributions, like Ubuntu, Fedora, and Mandriva, have already adopted a time-based release schedule, meaning that releases are not done on a feature basis, but according to a pre-determined time schedule. The Debian project has announced that it has adopted a time-based release schedule too.

But it doesn't do that at all! Just having a predictable feature-freeze cycle doesn't really do anything to make releases more predictable, really, because there's still a bugfix period. In the last few Debian releases (well, ever since Woody, really), that bugfix period was quite lengthy.